First experience of use of semen from the national cryobank as a management tool of genetic diversity in local pig breeds

Preservation of genetic variability of local pig breeds lies on a rigorous management of matings. Semen stocks preserved in the national cryobank constitute a patrimonial safeguard intended to reconstitute breeds in case of extinction. The goal of the present experience is to use frozen semen of the national cryobank to manage genetic diversity in farms, thus showing the complementarities of in situ maintaining of local breeds and ex situ cryopreservation. Sows of Porc Blanc de l’Ouest (PBO) and Bayeux breeds have been herded together to be inseminated with semen from the cryobank. Animals have been chosen according to the coefficients of coancestry in order to give birth to animals lowly related to the active population. Four PBO sows farrowed 28 piglets of which 14 males. Four boars and 9 gilts born from frozen semen have been kept for reproduction on farms and 2 boars entered an AI centre to complete the national cryobank. On the other hand, only one Bayeux out of 7 farrowed.This poor performance can be linked to parity (multiparous) and sow’s behaviour in group, to inbreeding of sows and to sanitary problems. As far as breeding conditions are well controlled, frozen semen can be used to manage genetic variability of breeds in conservation.